Method for preparing prevailingly to substantially isotactic crude polymerizates of butene-1



United States Patent METHOD FOR PREPARlNG PREVAILINGLY TO SUBSTANTIALLYISOTACTIC CRUDE POLYM- ERIZATES OF BUTENE-l Giulio Natta, Piero Pino,and Giorgio Mazzanti, all of Milan, Italy, assignors to MontecatiniSocieta Generale perl llndustria Mineraria e Chimica, a corporation oflta y No Drawing. Original application Nov. 30, 1955, Ser. No. 550,164.Divided and this application Aug. 7, 1958, Ser. No. 753,625

' 3 Claims. (Cl. 260-933) This is a division of pending applicationSerial No. 550,164, filed Nov. 30, 1955.

This invention relates to a new process for the selective polymerizationof certain unsaturated hydrocarbons. More particularly, the inventionrelates to a process for producing, at will, polymers of unsaturatedhydrocarbons which are predominantly to exclusively crystalline orpredominantlyto exclusively amorphous.

The unsaturated hydrocarbon polymerized has the formula CH =CHR in whichR is a saturated aliphatic, an alicyclic or an aromatic radical. Theunsaturated hydrocarbons may be polymerized alone or in admixture withone another, or in mixtures with small amounts (l-15%) of anothermonomer copolymerizable therewith. In the formula given, R may be inspecific modifications, an alkyl, cycloalkyl or aryl radical.

One object of this invention is to provide a new process forpolymerizing the unsaturated hydrocarbons whereby it is possible toobtain, at will, polymers having a predetermined amorphous tocrystalline ratio.

Another object is to provide an improved method for polymerizing theunsaturated hydrocarbons wherein the polymerization is carried out inthe presence of and with the aid of a polymerization catalyst in apredetermined state of aggregation and predetermined state of dispersionsuch that the mechanism of the polymerization is influenced and polymersof predetermined amorphous to crystalline ratio are selectivelyproduced.

In our pending applications Serial Nos. 514,097, now

abandoned, 514,098 and 514,099, all filed on June 8, 1955, we havedescribed new, regular, linear head-totail polymers of the unsaturatedhydrocarbons as well as an improved method for producing the same.

The method described in said application Ser. No. 514,098 involves theuse of polymerization initiators or catalysts as described in theBelgian Patent No. 533,362 for the polymerization of ethylene topolymers of high molecular weight. 7

Those catalysts are prepared by reacting a catalytic heavy metalcompound and a catalytic metal alkyl compound together in the dissolvedstate.

The catalytic metal alkyl compound used in preparing the catalystcomprises a substance or mixture of substances consisting of simple andcomplex compounds the molecules of which contain as a central atom anelement from the second and third columns of the Periodic Table, i.e.,beryllium, magnesium, zinc, cadmium, and other elements of the secondgroup, and aluminum and other elements of the third group.

The valences of the aforesaid central atom are linked to the same ordifferent alkyl radicals such as ethyl, propyl, butyl, etc. One valenceof the central atom may be satisfied by halogen or an alkoxy radicalsuch as ethoxy.

The catalytic heavy metal compound used in the preparation of thecatalyst consists of a compound or a mixinfra-red spectra.

Patented July 27, 1965 of titanium, zirconium, hafnium, thorium,vanadium,

tantalium, niobium, chromium, molybdenum, tungsten and uranium.

We have found, further, as set forth in our copending Nos. 514,097,514,098 and 514,099, of which-the present application is acontinuation-in-part, the polymers of the unsaturated hydrocarbonsproduced with the aid of the catalysts prepared as described above are,initially, mixtures of linear, head-to-tail polymers havingsubstantially no branches longer than R. The mixtures comprise, mainly,amorphous and crystalline polymers in varying amounts.

Depending on their steric structure and molecular weight, these polymersexhibit very ditferent characteristics. ,The amorphous polymers haveviscous elastic properties which lie between those of a highly viscousliquid and those of an unvulcanized, non-crystallizable elastomer, whilethe solid, highly crystalline polymers, which can be oriented bydrawing, are fiber-forming.

The polymers we obtain, which as pointed out in our copendingapplications supra are mixtures ofilinear, head-to-tail amorphous andcrystalline polymers having no branches longer than R are unique in thisart. That both types of polymers are linear is shown by their Forexample, in the case of our polypropylene, both the amorphous andcrystalline polymers have similar infra-red spectra which are completelydifferent from the infra-red spectra of the known branched polypropylenein which the branches are longer than R.

When monomer units some of which contain an asymmetric carbon atomhaving an I configuration and some of which contain an asymmetric carbonhaving a d configuration recur statistically along the polymer chain,

as is the general case for all known vinyl polymers, the polymer may beconsidered as a copolymer of the two types of structural units. If thesubstituent R is much larger than an H atom, the polymer (or copolymerin the sense just explained) is substantially non-crystalline and doesnot have any 1st order transition temperature. Prior to our inventionand discovery as disclosed in our above-identified copendingapplications, the only known example of a vinyl polymer existing in bothan 1 amorphous and in a crystalline form were the polyvinyl ethersprepared by Schildknecht and co-workers (Ind. Eng. Chem, 40 (1948),2104; ibid., 41 (1949), 1198, 2891). Those polyvinyl ethers are, ofcourse, quite different from the polymeric products we have disclosed.

As we have shown in our applications Ser. Nos. 514,097 1 II II II II IIor as such in the model of a portion of such a macromolecule which isgiven in each of our said pending applications and which model isrepeated hcreinbelow.

When all the .R groups of a plurality of chains show the above-mentionedregular arrangement, the polymers tend to adopt a crystalline structure.This is confirmed by examination with X-rays. We shall refer to theregular enchainment of the asymmetric carbon atoms in the main chain,whichis a basic condition for crystallinity of our polymers, asisotactic.

Our linear regular head-to-tail macromolecules having substantially nobranches longer than R and the main chain of which has substantially astructure of the kind illustrated in the model below (isotacticstructure):

(Model of a portion of the main chain of a crystalline polyalpha-olefinaccording to the Bresent invention, arbitrarily fully extended in aplane in w ich model the R substituents on the tertiary C atoms are allabove and their H atoms below the plane of the chain.)

are recognized in the art (following us) as isotactic macromolecules,whereas our macromolecules having substantially no branches longer thanR and in which the asymmetric carbon atoms of the two possible stericconfigurations have a substantially random distribution along the mainchain are recognized in the art (following us) as linear, regularhead-to-tail atactic macromolecules.

We have adopted the new term isotactic for identifying the structure ofthe -kind shown in the model, the macromolecules having substantiallythat kind of structure, and polymers consisting of these macromoleculessubstantailly having that kind of structure (see,-for example, the Nattaet al. communication to the editor of the Jr. of the Amer. Chem. Soc.,published in said Journal on March 20, 1965, received for publicationDecember 10, 1954; and the Natta article published in the Journal ofPolymer Science, April 1955, vol. XIV, issue No. 82, pp. 143-154,received for publication on February 17, 1955).

The main chain, when in the crystalline state, assumes a coiledconfiguration, the spiral having a pitch corresponding to a definitenumber of monomer units, generally three. in such case, all bondsbetween the R groups and the main chain have the same angle ofinclination relative to planes perpendicular to the axis the spiral.

On the other hand, whenever the polymerization leads to a randomdistribution of the orientation of the side chainin relation to theplane of the main chain, an amorphous product results.

If the side chains, i.e., the groups R, are of considerable lengthcompared with the distance of the carbon atoms in the main chain fromone another, and if they possess a great mobility, said chains willobstruct the arrangement of a plurality of chains to form a crystal. Themelting point of the crystalline polymers of the linear alpha-olefinesgenerally decreases by increasing length of the R groups. Polymerscontaining isotactic chains generally show, besides a tendency tocrystallize, also greater density, higher softening or meltingtemperature and lower solubility, compared with the non-isotacticproducts of equal molecular weight.

If the arrangement of asymmetric carbon atoms is isotactic crystullinityof the polymers occurs already at relatively low molecular Weights,e.g., from about 1000 upward.

Although we were able'to produce the polymerscom- '4. prising themixtures of amorphous and crystalline polymers from the unsaturatedhydrocarbons using the catalysts described above, no method wasavailable for steering the polymerization so as to predetermine theratio of the amorphous polymers to crystalline polymers contained in thepolymerizate we obtained. Such steering is accomplished by the processof the present invention according to which we produce polymerizates ofpreselected character, and whichconsist prevailingly of thecrystallizable polymers. or which consist prevailingly of the amorphouspolymers.

The present process is based on our discovery that the formation of thehigher proportions of amorphous polymers, or the formation of higherproportions of crystalline polymers, depends in general on the followingphysical and chemical factors with, respect to the catalyst.

The critical physical factors are:

(1) The state of aggregation of the the polymerization aid and of'theheavy metal compound used in its preparation.

(2) The state of dispersion of the-polymerization aid I in. the solventin which the polymerization is performed.

The critical chemical factors are:

(1) The nature of the functional groups bound to the heavy metalcontained in the polymerization aid.

(2) The nature of the alkyl group or gorups as well as the presence orabsence of other elements, such as halogen or oxygen in the metal-alkylcomponent used for preparing the polymerization aid.

(3) The valency of the heavy metal atom in the heavy metal compound usedfor preparing the polymerization aid. i

Other factors to be taken into consideration in the process of theinvention for selectively polymerizing unsaturated hydrocarbons so as tocontrol the course of the polymerization and steerf the same to obtaineither higher proportions of the crystalline polymers or higherproportions of the amorphous polymers will become apparent from thedetailed discussion of the invention which follows.

According to a main feature of ourinvention, polymerizates consistingsubstantially wholly of the crystalline polymer of the unsaturatedhydrocarbons are obtained by 7 using, for the preparation of thepolymerization aid, a solid, crystalline heavy metal compound in whichthe heavy atoms have a valence lower than the maximum valence which theheavy metal should possess in accordance with the Periodic Table.

The heavy metal compound must be capable of reacting, at least on thesurface, with the metal-alkyl. However, when preparing a catalyst foruse as aid in the production of isotactical polymers, this reactionshould not lead to the destruction of the crystal lattice originallyexisting in theheavy metal compound.

On the other, hand, the proportion of amorphous polymers in thepolymerization products. increases if a heavy metal atom in the heavymetal compound is of maximum valence and increases further withincreasing dimensions of the anionic groups containedin the heavy metalcompound.

The chemical nature of these anionic groups has also a considerableinfluence. Heavy metal compounds which, by reacting with the metal-alkylcompounds, give amorphous products that are easily dispersible in thereaction larity of structure resulting from the distributionof its atomsin a crystal lattice.) The best catalysts for the production ofisotactic polymers are obtained, in fact, from a solid crystallinecompound (e.g., TiCl or TiCl (By crystalwhich in reacting with themetallo-organic compounds does not undergo destruction of its crystallattice.

The catalyst prepared, for example, from TlCl3, which yields,preferentially, isotactic polymers, shows in fact the same violet coloras TiCl itself. The percentage of isotactic polymers in the resultingproduct is, in general, highest when the polymerization agent isprepared by starting with a pure, non-oxidized, non-hydrated TiCl whichis substantially free of TiCl On the other hand, when catalysts preparedfrom a liquid compound of a heavy metal in the stage of maximum valence(such as, for instance, TiCl are used, there is obtained, even in thepresence of a dispersing agent, a small portion of isotactic polymer inthe resulting product. This can be explained by assuming that the black,solid precipitate consisting of a titanium compound of lower valence,which is formed in the reaction between T iCl, and metallo-organiccompounds, possesses at least in part the regular structure ofcrystalline substances.

When compounds containing groups of various kinds bound to the Ti atom,such as the Ti(OR),,Cl. compounds, are reacted with metallo-organiccompounds, the resulting polymerization agents are generally of lessregular structure and, therefore, lead to predominantly nonisotacticpolymers.

Considering, for example, a heavy metal compound wherein titaniumrepresents the heavy metal, the following Table I will show that,starting with titanium dichloride as the lowest stage of valence andending with compounds containing large anionic groups such as (0B).; or(OR).,, a whole scale of heavy metal compounds is available whichpermits of the selection, at will, of a compound which, when used forpreparing the polymerization agent, will yield a polymerizate containingpredetermined proportions of the crystalline polymers and of theamorphous polymers. 1

TABLE I Heavy metal compound Polymerization When preparing thepolymerization aid from a solid titanium compound such as powderytitanium trichloride, suspended in, e.g., a hydrocarbon, adding theertoa metal alkyl compound such as tricthyl aluminum or diethyl aluminummonochloride, and subsequently heating the suspension to 50-90 C., acatalyst is obtained which permits control of the polymerization of theunsaturated hydrocarbons so that substantially crystalline polymers areobtained.

Instead of'titnnium trichloride, other solid, crystalline compounds oflow valency may be used. For instance, the corresponding compound ofdivalent titanium (TiCl l, is equally suitable for the production ofcatalysts for use in making substantially crystalline polymers of thealpha-olcfines.

Titanium tribromide, however, even though it is a crystalline solid,yields, as compared to titanium trichloride, a larger proportion ofnon-isotactic polymers. This is due to the fact that TiBr is slightlysoluble in the hydrocarbon solvent used, and therefore reacts with themetalloorganic compounds, at least in part, in a state of noncrystallinity, namely while being dissolved in the hydrocarbon.

Titanium tetrabromide behaves similarly to the tetrachloride, yielding apartially amorphous and partially crystalline polymer. The high meltingpoint of TiBn, has practically no influence since under the reactionconditions it is completely soluble in the solvent used.

In a similar manner, the ratio of amorphous to crystalline portions inthe resulting polymerization product can 1 On the other hand,predominantly or wholly amorphous polymers are obtained with catalystsprepared by using as the heavy metal compound substances such asvanadium oxytrichloride VOCl or vanadium tetrachloride, wherein vanadium-is pentaor tetravalent, respectively, zirconium tetrachloride, chromiumoxydichloride CrO Cl and the corresponding compounds of the otheraforesaid heavy metals.

The method according to this invention of preparing the polymerizationagents suitable for the production of sub-.

stantially crystalline polymers from solid, heavy crystalline metalcompounds wherein the heavy metal atom has a valence lower than themaximum one, offers several advantages compared with other methods ofpreparing such catalysts. For instance, in preparing the catalysts fromthe aforesaid heavy metal compounds, smaller quantities ofmetallo-alky'l compounds are required for activating the catalystsurface.

In general, it can be stated that if the heavy metal compound is solubleor partially solube in the liquid medium in which the catalyst isprepared, the catalyst will tend to disperse readily in thepolymerization medium and will favor the production of amorphouspolymers of the unsaturated hydrocarbon, whereas it the heavy metalcompound .is crystalline and insoluble in the medium in which thecatalyst is prepared, the catalyst will contain crystalline parts andwill be difficulty dispersible in the polymerization medium and favorthe production of crystalline polymers of the unsaturated hydrocarbon.

The medium in which the catalyst is prepared and the polymerizationmedium may be the same, i.e., the liquid monomeric unsaturatedhydrocarbon to be polymerized, with or without admixture with a solventfor the metal alkyl compound which solvent does not enter into thepolymer-ization reaction. 7

The following hypothesis of the mechanism of the reaction which, webelieve, take place in the formation,

of the catalyst from the heavy metal compound and the metal alkylcomponent, and the subsequent polymeriza-"* metal compound used, one ofthe following two reactions will take place:

(b) 'ric1,+2AlR,- Tic1,R+2A1R,c|+R

From the reaction mechanism indicated, it can be seen i readily that theconsumption of metal alkyl in the second case, that is when using aheavy metal compound in whichv the heavy metal is of maximum valency, istwice that in the first case using directly a heavy metal compound inwhich the heavy metal is already in a reduced state of valency.

In practice, the consumption of metallo-organiccompound is even less,because in the case of TiCl; the reaction is limited to the surface ofthe TiCl; crystals.

As a further advantage, when it is desired to produce substantiallycrystalline polymers, the preparation of the catalyst according toEquation a requires only one step, while in the preparation of thecatalyst according to Equation b, the additional step of mechanicalfractionation is required. By this step, the solid fraction of thecatalyst is separated from the liquid or dissolved portion thereof andonly the solid fraction is used if a polymerizate consistingsubstantially of isotactic crystalline macromolecules is to be obtainedas shall be explained in detail hereinafter.

n the other hand, it was found that a mixture of the amorphous polymersand the crystalline polymers can be obtained from unsaturatedhydrocarbons by using the unfractionated polymerization agents which areobtained by using a preferably soluble or liquid heavy metal compound,such as titanium tetrachloride, titanium tetrabromide, vanadiumtetrachloride and the like.

If such heavy metal compounds are reacted with a metal alkyl component,a change of valence will take place in the heavy metal compound. In thecase of titanium tetrachloride, this change of valence can be assumed totake place according to the following scheme:

, Steps c and d are fast reactions in which a strong gas [Change ofcrystallinlty with titanium substituent and The presence of the lattergroups in the final catalyst long chains of carbon atoms,qwhich can beintroduced.

into the final catalyst by being previously bound either to the initialheavy metal compound or to the metal alkyl compound. Such groups shouldhave more than four and preferably from six to sixteen carbon atoms.

In the following Tables 2 to 4, the results of a number ofpolymerization tests are compiled which show the influence of suchlyophilic groups in the metal alkyl component of the catalyst on theproportion of crystalline and amorphous polymers in the finalpolymerizate.

All tests reported in the tables were performed under comparableconditions. The molar ratios between titanium tetrachloride and thealuminum alkyl compound were in the order of 122.5 to 1:10 and in thecase of titanium trichloride to the aluminum alkyl compound of the orderof 1:2.

It is apparent, from these tables, that the percentage of amorphouspolymers in the final polymerization product increases with anincreasing number of carbon atoms in the alkyl groups linked toaluminum, beginning with a number of 2C atoms in the alkyl radical.

With thesolutions or high-degree dispersions obtained when lyophilicgroups are present in the initial heavy metal compound or in the metalalkyl component, no precipitate can be isolated by mechanical steps suchas filtration and the like.

As can be seen from Table 2, the formation of a n0ncrystalline catalystand its dispersion are also favored by using heavy metal compoundshaving alkoxy substituent groups, even of relatively short chain length.,For instance, dibutoxy titanium dichloride Ti(OC I-I Cl also leads tothe formation of a catalyst whieh yields predominantly amorphouspolymerizates of the unsaturated hydrocarbons.

TABLE 2 nation of propylene. (Percentage of crystalline traction intotal polymer obtuined)] Propylene TiGh, TiCl; 'IiCli (004110 012Ti(OCiH0);C1 Ti(OC4Hv)4 TKOH),

Al Ethyl; (1) (2 3,4) (0) (1 (17) (lo) 18 75 85 I 47.8 35.1 10 TracesTrfrcei;

(17) Al Propyl; 2 'ruocuim 4% Al Butyli (6) l1) About 30 A1 Hexyh (7)(12) Al Hexadecyli.--. (8) (13) bt 'iIhr:l number in parenthesesindicates the specific example given below from which the result shownwas 0 a no The formation of amorphous polymerization products is alsopromoted by using, in the preparation of the catalyst, metal alkylcomponents in which the alkyl groups exhibit strongly lyophilicproperties. I

Table 3 shows that the above mentioned rules for steering thepolymerization process to obtain products of more or less predominantlycrystalline character also prevail in in polymerization of the higheralpha-olefines, such as butene-l.

It can be seen from this table that the ratio of crystalline toamorphous solid polybutene-l is greater when using TiCl than when usingTiCl, as one of the catalyst-forming components. The influence of thelength of the alkyl' radical in the aluminum alkyl compound is lesspronounced than in the polymerization of propylene.

substituent in Installs-organic compound polym cr- TABLE 3 [Change ofcrystallinity with titanium suhstltuent and substitucut innictallo-orgunlc compound. Polymerization of butene 1 (percentage ofcrystalline fraction in total polymer obtained).]

Butcuod 'liCh TiCh (21, 218) Al Ethyl: lg

Al Propyl; i -2 Al Butyh Al llexadecyl; 2%

The number in parentheses indicates the specific example given belowfrom which the result shown has been obtained.

Table 4, on the other hand, illustrates the influence of the presence ofhalogens as well as isoalkyl groups in the metal organic component onthe composition of the final polymerization products. The presence ofsuch halogen substituents in the metal organic component tends toincrease the amorphous fraction of the final product, over that in theproduct obtained with the corresponding metal organic componentcontaining only straight chain alkyl groups, while isomery does notchange the ratio in the polymer.

TABLE 4 [Influence of chlorinated or ramltjed (branched) radicalsubstituents in the metallo-alkyl compound on the degree ofcrystalllnity of polymers of propylene.- Polymerization agents obtainedfrom titanium trlchloride and titanium tetrachloride.

The number in parentheses indicates the specific example given belowfrom which the result shown has been obtained.

As has been stated above, we have further discovered that the state ofaggregation or the phase in which the finally obtained catalyst isbrought into contact with the unsaturated hydrocarbon monomers to bepolymerized is of considerable importance in controlling the formationof a polymerizate having a higher content of either the crystalline orof the amorphous components.

We assume that when these solid, crystalline catalysts (for instancethose containing titanium as the heavy metal, obtained by reacting TiClwith triethyl-aluminum) show, to a given extent, solid, regular surfacesclose to reactive metal alkyl linkages, they are particularly adaptedfor acting as catalysts in the formation of polymers having an isotacticarrangement of the asymmetric carbon atoms in the main chains andcorrespondingly a crystalline nature.

If, on the other hand, the surface structure of the catalyst particlesis iregular, as in a micellar dispersion in a liquid, such catalysts actas polymerization agents which yield non-isotactic and correspondinglyamorphous polymerization products.

This is confirmed by a study of Table 5, which shows the influence ofthe halogen linked to the heavy metal in the heavy metal compound, whenthe heavy metal is in a lower as well as in the maximum state ofvalence. It is apparent from this table that in the case of bromide 75and iodide as the starting heavy metal component a change of valencefrom 4 to 3 does not result in increased crystallinity in the resultingpolymer but that the state of dispersion of the polymerization agent inthe reaction medium is the decisive factor. Thus the polymerizationagent obtained with Til yields a lower content of crystalline polymerthan Til because it is more finely dispersed in the reaction medium thanthe polymerizing agent obtained from the latter substance.

In the case of TiBr the two factors, valence and state of dispersion,balance each other, so that the degree of crystallinity obtained in thefinal polymerization product is the same.

TABLE 5 [Influence of halogen in titanium halide on degree ofcrystalllnity o propylcnc. polymer. Polymerization agent obtained fromaluminum trlethyl and titanium trihalido or tetrahalidc] The number inparentheses indicates the specific example given below from which theresult shown has been obtained.

The influence exerted by the nature of the polymerization aid orcatalyst in the polymerization of the unsaturated hydrocarbons oralpha-olefines can be explained in the following manner:

During the polymerization process, using a crystalline agent, the alkylchain of the heavy metal-alkyl linkages grows by reaction with themonomeric olefine molecules by inserting the latter into the linkagesbetween the heavy metal atoms and the alkyl groups present on thesurfaces of the crystals so as to form a growing paraflinic mole- 'culewhich, due to its saturated nature, is less strongly adsorbed to thecrystal surfaces than the olefinic monomer. Successive molecules of themonomer are adsorbed on the crystal surfaces and can then insertthemselves between the heavy metal'alkyl groups linkages.

If the successive monomer molecules are all oriented in the same Way, apolymerization product of very regular structure and, therefore,crystallizable, will be obtained. On the other hand, if the molecules ofthe monomer are not similarly oriented due to a lack of orientingsurface on the catalyst, an amorphous, non-crystallizable polymerizalionproduct results.

We have made the further discovery that a titanium containing catalystor a catalyst containing another heavy metal of the kind described, ofmaximum valence, prepared as described in our copending application Ser.No. 514,098 and comprising both coarse crystalline particles and finelydispersed to dissolved or liquid portions can be separated into severalfractions one of which consists of the coarser, more crystallineparticles which, when used as a catalyst in the polymerization of theunsaturated hydrocarbon, yields chiefly or exclusively isotactic and,therefore, crystallizable polymers, and the other of which comprises amicellar dispersion or finer, less crystalline particles which yieldpredominantly or exclusively amorphous, non-crystallizable polymericproducts, i.e., polymers having mainly non-isotactic chains.

As described in said pending application Ser. No. 514,098, when theunfractlonatcd catalyst is used, a mixture of amorphous and crystallinepolymers is obtained. However, when the coarser, more crystallineparticles are separated, for instance by filtering the catalystcontaining medium through filter plates having relatively small pores,the filtrate containing the finer, more highly (lispcrscd particles canbe used as aid in the selective polymerization of. the unsaturatedhydrocarbons to substantially completely amorphous products. Thisseparation is accomplished, for example, by the use of a porous glassplate filter having pores of to microns diameter. Catalyst particles ofa size to be retained by a filter having pores of a diameter between 5and 15 microns yield predominantly to exclusively crystalline polymersof the unsaturated hydrocarbon while those which pass through such poresyield predominantly to exclusively amorphous polymers.

As shown in Table 6 below, in the case of'catalysts obtained from TiClthe fraction remaining on the filter can be used as a catalyst forproducing polymerizates of higher (54%) crystalline polymer content thanis contained in polymerizates produced with the aid of theunfractionated catalyst. The latter polymerizates have a crystallinepolymer content of only about TABLE 6 [Amount of erystallinity inpolynlefines obtained with precipitate and filtrate of catalyst preparedfrom heavy metal tetrahalide and alumin um triethyl] I Completelyamorphous.

If the precipitate on the filter is further fractionated by filtrationthrough a filter having pores of a larger diameter (up to microns), aprecipitate is obtained on the filter which, when used as a catalyst inthe polyrn erization of the unsaturated hydrocarbons, will yieldpolymers having a much higher content of crystalline product.

Other known separation methods, e.g., decantation, flotation orcentrifuging may be used to separate the more crystalline (generallyheavier) portions of the catalyst from the amorphous (generally lighter)portions thereof.

It will be apparent that the present invention provides methods forpreparing various catalysts which can be used selectively for theproduction of substantially completely crystalline olefine polymers;mixtures having a predetermined content of crystalline to amorphouspolymers; or substantially completely amorphous polymers of theunsaturated hydrocarbons.

Tables 7, 8 and 9 illustrate the various aspects of our invention asapplied to various heavy metals of the groups described above, otherthan titanium. These tables confirm the influence of the various factorsexplained hereinabove, using heavy metal compounds other than titaniumcompounds.

TABLE 7 1 2 TABLE 8 [Degree oi: ctgtstallinity in propylene polymersobtained with pulyinerlzation agent prepared from heavy metal halides 0tditl'erent; ralenees and aluminum triethyl] TABLE 9 [Degree oferystallinli'y in lnttene-l polymers obtained with puLcmm-math-n agentprepared from h avy metal hullden of tllllfl't'llt valences and aluminumtriethyl] It may be noted that the use of alkyl-aluminum compoundscontaining alkyl groups of high molecular weight has a considerableinfluence in reducing themolecular weight of the polymer, when TiCl isused. In that case, the alkyl groups of high molecular weight have ananti-coagulating efl'cct on the catalyst which is formed. When solidTiC1 is used, the anti-coagulating effect is not exhibited.

The following examples illustrate in detail certain specific embodimentsof the invention and explain the manner in which the above tables havebeen obtained, it being understood that these examples are not intendedas restrictive of the scope of the invention.

Example I Two steel balls, :1 glass vial containing 7.2 g. ofcrystalline titanium dichloride and a solution of 11.4 g. of triethylaluminum in 500 cc. of n-heptane are introduced under nitrogenatmosphere into a 2150 cc. autoclave. The autoclave is then heated to 82C. and at that temperature 140 g. of pure propylene are introduced. Theautoclave is then set in motion in order to break the vial. This leadsto the formation of a coarsely dispersed solid polymerizing agent. Theautoclave is kept in motion for about 10 hours at to 85 C. Thereafter,the

[Decree of erystallinity of propylene and hutene-l polymers obtainedwlth various heavy metals of ditl'erent valency, and with differentmetal nlkyl compounds] Propylene polymerization ZrCl4 V014 V061;

Bntene-l polymerizatlon VCli Isl Ethyh Al lropyl;

Al Dccyh Al llexadecyh 13 gases are vented and the unpolymerizedpropylene is collected. 7

After pumping methanol into the autoclave, the polymer is taken out as awhite powder and is purified with acids to eliminate the inorganicproducts present. About 115 g. of a white powder are obtained withconversion of 82% on the used propylene.

The polymer obtained is fractionated by hot extraction with solvents.

The oily, low molecular weight polymers, 5.8% of the obtained product,are removed by extraction with hot acetone. Extraction of the residuewith hot ether dissolved an amount of polymer (8.3% of the totalpolymer) which consisted of solid polypropylene, amorphous under theX-rays, having an intrinsic viscosity of 0.47 in tetralin solution at135 C.

By hot extraction with n-heptane a fraction was then obtained(corresponding to 10.4% of the total) consisting of polypropylene havingan intrinsic viscosity of 0.57 and more than 50% crystalline under theX-rays. The extraction residue, corresponding to 75% of the totalpolymer, consists of a highly crystalline polypropylene having anintrinsic viscosity of 1.86. The raw polymer obtained had, therefore, acrystallinity of at least 80%.

Example II A glass vial containing 2 g. TiCl in 30 ml. n-heptane isintroduced into a 435 m1. autoclave together with a steel ball (1 inchdiameter) (to break the vial at the moment the polymerization is to bestarted). A solution of 5.7 g. triethylaluminum in 50 ml. n-heptane isthen introduced into the autoclave under nitrogen atmosphere and theautoclave is heated up to 70 C. At this moment 103 g. of liquidpropylene are admitted and soon afterwards the autoclave is put inmotion in order to break the TiCl vial.

A slight temperature increase is noticed, while the pressure decreasesslowly but continuously. After 6 hours, during which the temperature iskept between 80 and 90 C. when a pressure decrease is no longerobserved, 50 ml. methanol are pumped into the autoclave in order to decompose the catalyst, and the residual gases, containing 10 N1 ofpropylene, are released. From the autoclave a solid, compact mass isdischarged, which is first purified as described in the foregoingexample and then with concentrated HCl while swelling the mass withboiling toluene. The product is then coag'ulated with methanol, filteredand washed with methanol and dried by heating under vacuum.

82 g. of polymer are obtained, corresponding to a 79.6% conversion ofthe employed propylene. Said polymer is made up mostly (85%) ofcrystalline polypropylene, which may be separated from thenon-crystalline products by extraction with solvents.

The amorphous portion is entirely soluble in acetone; the greatestportion soluble in warm ether has a softening point of 100 C., anintrinsic viscosity of 0.685 and a molecular weight of about 18,000. Thecrystalline portion, insoluble in warm heptane, has a softening point of165 C., an intrinsic viscosity of 2.39 and a molecular weight about120,000.

- Example 111 Into an oscillating 500 cm. autoclave, fitted with ajacket for circulation of heating oil provided with a control device forkeeping the temperature constant within one degree, are introduced undernitrogen atmosphere 0.98 g. TiCl in 220 cm. of anhydrous n-heptane.After evacuating, the solvent is saturated with pure propylene (98.5%)under a pressure of 1000 mm. Hg above the atmospheric pressure, bringingat the same time the temperature inside the autoclave to 70 C. Theautoclave is kept in motion at 70 C. for 90 minutes. Under propylenepressure a solution of l cm. triethyl-aluminum in 30 cm; n-heptane isthen added. This leads to the formation of a coarsely dispersed solidpolymerization agent. For a period of 4 hours a continuous feed ofgaseous propylene is then maintained, under a constant pressure of 1000mm. Hg above atmospheric pressure.

After about 2 hours from the addition of triethylaluminum it can benoticed that the polymerization ratio corresponds approximately to anadsorption of 11.5 g. propylene per hour and per g. TiCl After saidperiod of time the product is taken out and purified as usual. In thisway 42 g. propylene polymer are obtained, with a high content ofcrystalline product (about Example IV The autoclave of the precedingexample is charged, in

nitrogen atmosphere, with 1.05 g. TiCl and with a solution of 3.25 g.triethyl aluminum in 250 cm. n-heptane. This leads to the formation of acoarsely dispersed polymerizing agent. The autoclave is then put inmotion and kept for 4 hours at 70 C. The nitrogen is then replaced withpropylene, saturating the solvent under a constant pressure of 1000 mm.Hg above atmospheric pressure. After two hours the polymerization rate.corresponds to the adsorption of 11.4 g. propylene per hour and per g.TiCl The amount and structure of the obtained polymer correspond tothose obtained in Example III.

Example V Into a 435 cm. oscillating autoclave are introduced twostainless steel balls and a vial containing 1.85 g. (0.012 mole)titanium trichloride; a solution of 3.9 g. tripropylaluminum in cm.heptane is then added under nitrogen. The autoclave is heated to 73 C.and at this temperature 90 g. propylene are introduced. The autoclave isthen set in motion so as to break the vial. This leads to the formationof a coarsely dispersed catalytic agent. After 10 hours reaction at atemperature between 70 and 75 C., the reaction product is taken out. Itappears as a solid very compact mass containing a large amount ofadsorbed solvent. The purification is carried out by washing withdiluted hydrochloric acid, as described previously. 72 g. of a solidwhite polypropylene are obtained, which are then fractionated byextraction with hot solvents.

The acetone extract corresponds to 3.5% of the obtained polymer and isformed by oily, low molecular weight products.

The ether extract corresponds to 13.3% of the total, and is formed of asolid amorphous polypropylene, showing an intrinsic viscosity of 0.725(in tetralin at C.) which corresponds to a molecular weight of about20,000.

The heptane extract corresponds to 11.4% of the total and consists of apolypropylene having an intrinsic viscosity of 0.9, i.e., a molecularweight of about 28,000. Under the X-rays, this fraction appears toconsist of polypropylene with a crystallinity higher than 50%.

The extraction residue is 71.8% of the total, and is formed of a highlycrystalline polypropylene having an intrinsic viscosity of 3.08, i.e., amolecular weight of about 180,000. The raw polymer had therefore a totalcontent of crystalline polypropylene of at least 77.5%.

Example V1 3.7 g. titanium trichloride and a solution of 9.9 g.tributylaluminum in 250 ml. heptane are introduced in a 2080 ml.autoclave. 220 g. of a propylenepropane mixture containing 92% propyleneare added and the autoclave is heated, under stirring, to 90 C.

At this temperature a rapid pressure fall takes place. The autoclave iskept in motion for 5 hours; the polymerization product is then taken outand g. polypropyl- 1 5 enc are obtained, which are fractionated by extraaction with hot solvents, with the following results:

The obtained polymer had therefore a crystallinity of about 60%.

Example VII A 435 cm. autoclave is charged with two steel balls, a vialcontaining 1.85 g. TiCl and, in nitrogen atmosphere, a solution of 7.05(0.025 moles) trihexyl-aluminum in 100 cm. heptane. After heating to 85C., 92 g. propylene are added and the autoclave is set in motion. Afterkeeping the temperature between 95 and 100 C. for about hours, thereaction product is taken out and purified in the usual way.

83 g. of polypropylene are obtained, which are fractionated byextraction with hot solvents. The acetone extract corresponds to 11.8%of the total polymer and consists of oily products of low molecularweight. The ether extract is of the total and consists of solidamorphous polypropylene, with an intrinsic viscosity of 0.57.

The heptane extract is 19.2% of the total and has an intrinsic viscosityof 0.8. This fraction, when examined under the X-rays shows a content ofcrystalline polymer higher than 50%. The extraction residue correspondsto 54% of the total and is formed by a highly crystalline polypropylenehaving an intrinsic viscosity of 2.07. The total product has therefore acontent of crystalline polypropylene of about 64% Example VIII A 1100cm. autoclave is charged, under nitrogen atmosphere, with 1.85 g. TiCland with a solution in 100 cm. n-heptane of 17.5 g. of atrialkyl-aluminum having an average molecular weight corresponding totrihexadecyl-aluminum. The polymerizing agent occurs as a mixture ofrelatively coarsely dispersed and relatively finely dispersed particles.130 g. of a propylene propane mixture containing 91% propylene are thenadded.

The temperature is then brought to 90 C. and kept at this value forabout 10 hours. The obtained product weighs after purification, 115.2g., and is fractionated by extraction with hot solvents.

The acetone extract, 11.4% of the total polymer, is formed of oily, lowmolecular weight products.

The ether extract, 19.5% of the total, is a solid, amorphouspolypropylene, showing in tetralin solution at 135 C. an intrinsicviscosity of 0.65.

The heptane extract of the total, has a content of crystallinepolypropylene higher than 50%. This fraction has an intrinsic viscosityof 0.80.

The extraction residue, 49.1% of the total, appears, under the X-rays,as a highly crystalline polypropylene, and has an intrinsic viscosity of3.15. The total product has therefore a content of crystallinepolypropylene of about 59%.

Example IX About 600 ml. of solvent (heptane-isooctane mixture)containing 11.4 g. triethylaluminum are introduced into a 18/8 stainlesssteel autoclave of 2150 ml. capacity. 325 g. of propylene are added andthe mixture is heated up to 60 C.; then 3.6 g. titanium tetrachloridedissolved in 50 ml. solvent are admittcd into the autoclave. The

temperature rises spontaneously in a few minutes up to 113 C. and thenslowly decreases. When the temperature reaches C., 1.8 g. titaniumtetrachloride dissolved in 50 ml. gasoline are added. A further smallertemperature increase is then observed. The autoclave is kept inagitation for about two hours. It is cooled then to 60 C. and theresidual gases are released.

The polymerizing agent is decomposed by introducing into the autoclave150 g. of methanol. After stirring for a few minutes, the reactionproduct, consisting of a solid mass drenched with methanol and gasoline,is discharged. The product is slurried in ether and treated withhydrochloric acid to remove most of the inorganic substances, and isthen coagulated with methanol and filtered. Thus 282 g. of a white solidproduct are obtained having a softening point of about l30-140 C. Theyield of solid polypropylene on the introduced propylene is 87%; theyield on the converted propylene is higher than The polymer obtained isfractionated by hot extraction with solvents, using, successively,acetone, diethyl ether and n-heptane.

The acetone extract corresponds to 40.5% of the polymer obtained andconsists of a rubbery, amorphous solid. In tetralin solution at C. itshows an intrinsic viscosity equal to 0.49 (corresponding to a molecularweight of 11,000).

The heptane extract corresponds to 24.4% of the polymer obtained andconsists of a partially crystalline solid having an intrinsic viscosityequal to 0.95.

The residue which remains after said extractions amounts to 27.2% of thetotal polymer and consists of a powdery, highly crystalline solid havinga first-order transition point of about 160 C. In tetralin solutions at135 C. it shows an intrinsic viscosity equal to 1.77 (corresponding to amolecular weight of about 78,000).

Example X 530 ml. of gasoline containing 15.6 g. tripropyl aluminum and275 g. propylene are introduced into a 2150 ml. autoclave, which is thenheated up to 70 C. Thereafter, 3.6 g. titanium tetrachloride dissolvedin gasoline are added. The temperature rises spontaneously to 95 C.,then drops down again to 80 C. A further addition of 1.8 g. titaniumtetrachloride is made. The autoclave is then kept in agitation for fourhours while keeping the temperature at 80 C. By operating as in ExampleTX, 209 g. of solid polymer are obtained. The purified, unfractionatcdpolymer begins to soften at The yield is 75% on the introducedpropylene, and higher than 95% on the converted propylene.

The acetone extract corresponds to 7.1% of the polymer obtained andconsists of oily, low molecular weight products.

The ether extract corresponds to 32.4% of the polymer obtained andconsists of a rubbery, amorphous solid hav Example XI A solution of 10g. Al (WC- 11 in ml. n-hcptane is introduced into a 100 ml. autoclave;200 g. of a propylene-propane mixture, with 92% propylene, are then Whenexamined under the Xrays it has an intrinsic Percent of Intrinsic thetotal viscosity Remarks polymer Acetone extract 24. 8 Amorphous. Etherextract 36 0. 47 Solid amor hous. n-He tane extract 18.3 0.71 50% crystame. Best ue 20.9 1. 47 Highly crystalline.

The raw polymer had therefore a crystallinity of about 30%.

Example XII A solution of 28.8 g. (M of mole) of a trialkyl aluminum,having an average molecular weight corresponding to trihexylaluminum, isintroduced into a 2150 ml. stainless steel autoclave, previously driedand evacuated. 28.5 g. of liquid propylene are admitted, then theautoclave is put in motion and the heating started. Once the temperatureof 80 C. is attained, a solution of 3.8 g. TiCl in 40 ml. heptane isintroduced in'the reaction vessel. The temperature goes up spontaneouslyreaching in a few minutes 120 C., and then drops slowly again. When thetemperature is down again to 80 C., 3.8 g. more of TiCl dissolved in 40ml. heptane, are added. A further temperature increase occurs althoughsmaller than the previous one. The autoclave is shaken for 2 more hours,the gaseous products are then vented and finally about 100 ml. methanolare introduced in order to decompose the polymerization agent. Theresidual gases derived from the decomposition of the catalyst arereleased; in the autoclave remains a viscous solid mass, which isdischarged and purified by heating with ether and hydrochloric acid inorder to remove the inorganic substances present on the filter,resulting from the decomposition of the catalyst. The polymer swollen bysaid solvents is then coagulated with methanol, filtered and washed withmethanol. The solid mass left on the filter is then dried under reducedpressure at a temperature I below 100 C.

25 g. of polymer are thus produced, corresponding to an 87% conversionof the employed propylene. 73.8% thereof is made up of an amorphouspolymer, most of which, soluble in warm ether, shows the properties ofan unvulcanized elastomer. The ether-soluble portion when extracted withwarm acetone leaves an extraction residue having a softening point of 75C., an intrinsic viscosity of 0.33 (determined in tetralin solutions at135 C.) and a molecular weight of about 7,000.

The remaining 26.2% is formed of crystalline. polypropylene, the bulk ofwhich is insoluble in hot n-heptane, has a softening point of 150 C.,and intrinsic viscosity of 1.28 and a molecular weight of about 50,000.

Example XIII Proceeding as in Example XII, 70.2 g. of a trialkylaluminumhaving an average molecular weight corresponding to trihexadecylaluminumdissolved in 500 ml. heptane, and 350 g. liquid propylene are introducedinto a 2150 ml. autoclave. The autoclave is heated up to 67 C. whilekeeping it in agitation; the solution of 3.8 g. titanium tetrachloridein 40 ml. heptane is then injected under nitrogen pressure. Thetemperature goes up spontaneously to 110 C.

Once the temperature is down again to 100 C. a soluk 2 tion of 3.8 g.titanium tetrachloride in 40 ml. heptane is injected. About 5 hours fromthe start of-the polym-- erization 100 ml. methanol are pumped into theautoclave and the residual gases are vented.

Operating as in Example XII, the catalyst is decomposed and and afterpurification 338.7 g. of a solid polymer (corresponding to 96.5% of theemployed propyltrinsic viscosity of 0.5 and a molecular weight of about.11,000. The crystalline portion, insoluble in n-heptane,

has a softening temperature of about 150 C., an intrinsic viscosity of1.03 and a molecular weight of about 37,000.

Example XIV A sealed glass vial containing 9 g. dichlordbiutoxy titanium(TiCl (OC H and 3 steel balls are introduced into a 2150 ml. autoclave.mosphere the solution of 11.4 g. triethylaluminum in 500 ml. heptane isthen syphoned in the autoclave. After heating up to C., 275 g. of liquidpropylene are then added and soon afterwards the autoclave is put inmotion, keeping the temperature in the range 90-100 C. About 10 hoursfrom thestart of the polymerization, methanol is pumped into theautoclave and the unreacted gases are released. The reaction productextracted from the auto--,, clave appears as a viscous, nearly solid,greenish brown;

colored mass, which is purified as usual.

After purification, 54.2 g. polymer are separated, corresponding to a20% conversion of the employed propylene.

in warm ether.

The remainder (35.1%) is crystalline polypropylene,

which may be separated from the amorphous portion by means of successiveextractions with solvents.

Example XV Into an autoclave of about 2 liter capacity are introducedunder nitrogen a solution of 11.4 g. triethylalumium in 500 cm. heptaneand 190 g. propylene. The autoclave is heated to 64 C. and at thistemperature a solution of 0.03 moles titanium tributylate monochloridein 50 cm. pentane is injected under nitrogen pressure. The autoclave iskept in motion for about 8 hours at a temperature between 80 and C.After this time the reaction product is takcn out; after purificationand drying there are obtained 8 g. of a solid gummy polymer containingapproximately 10% of crystalline polypropylene.

Example XVI Example XV is repeated, using titanium tetrabutylate insteadof the tributylate monochloride, 5.4 g. of low molecular weightpolypropylene are obtained which contain only traces of crystallinepolymer.

Example XVII 11.4 g. Al(C I-l dissolved in 200 ml. heptane and 200 g.propylene are introduced, under nitrogen, into a 2150 ml. autoclave.After heating under stirring to 81 C. a solution of 0.5 g. titaniumtetraisopropylate is injected in the autoclave, which is then kept in'motion for about 15 hours at temperature between and C.

The reaction product is purified as usual, and 6 g. of' polymer areobtained. These are fractioned by extrac- Under nitrogen at- More thanhalf (64.9%) of the obtained product p is made up of amorphouspolypropylene, mostly soluble- 19 tion with hot solvents in the usualway, and the following results are obtained:

which are fractioned by extraction with hot solvents. The fractions areasfollows:

Pereent of Intrinsic Percent of Intrinsic the total viscosity Remarksthe total viscosity Remarks P y polymer Acetone extract e0 -tt...Amorphou Aoetene extract--.- 3.1 Low oily polymers. Ether extraet- 33t). 37 Htiolld nmor hous. Ether extract 29. 2 0.82 Amorphous solid. n-Hetime extrsc o 0.71 50% erys linen-Heptane extract 67. 7 2. 12Crystalline. Resl no 1 Highly crystalline. 10

Example XX-A The obtained polymer had therefore acrystallinityof abuot4%.

Example XVIII A glass vial containing 0.7 g. Ti(OH) and a solution of5.7 g. Al(C,H in 150 ml. n-heptane are introduced into a 435 ml.autoclave filled withnitrogen. 100 g. of a propylene-propane mixturecontaining 90% propylene,

are then added, the autoclave-is heated to 90 C., and set in motion inorder to break the vial. After 12 hours the polymerization product istaken out and the polymer is coagulated by adding methanol'and acetone.

2 g. of solid polymer and 35 g. of semi-solid and oily, low molecularweight products are obtained.

The solid products when examined under the -X-rays reveal acrystallinity of about 50%.

Example XIX I heated, under stirring, to 90C., and kept at thistemperature for 7 hours.

The polymerization product is then taken out and purified as usual.

61 g. of polybutene are obtained which are fractionated by extractingwith hot solvents, with the following reduced. The autoclave is kept inagitation at temperatures. 7

between 78-80 C. for 20 hours. Methanol is then pumped in and theunreacted gases are discharged.

From the autoclave a very viscous mass is discharged, which is entirelycoagulated by further addition of methanol and purified as usual. 29 g.of white solid polymer are obtained, which are fractionated throughextraction with hot solvents. 65% of the product is crystallinepolybutylene of a molecular weight above 30,000. v

The remainder is formed of wholly amorphous product showing theproperties of an unvulcanized elastomer.

When the run :is repeated employing as a catalyst a 7 mixture of TiCl,and trihexadecylaluminum,v a viscous product is obtained which is morefluid than the one of the preceding case, and formed in practice whollyby amorphous polybutene.

Example XIX-A 1.85 g. TiCl a solution of r 3.9 g. tripropylaluminum in100 ml. heptane, and 85 g. 'l-butene are introduced into a 435 ml.autoclave. The polymerization is carried out at temperatures between 90and 95. 60.5 g. polybutene are obtained, which are fractionated in theusual way.

The crystalline fraction, insoluble ,in hot ether, corresponds to 75% ofthe total product.

Example XX 6.5 g. TiCl in a glass vial and two steel balls areintroduced into an oscillating 1100 ml. autoclave. The autoclave isfilled with nitrogen and a solution of 19.8 g. Al(n-C H in 500 ml.n-heptane is then added. After heating to 85 C., 115 g. butene-l(Phillips pure grade) are added-and the autoclave is put in motion so asto break the vial.

The temperature rises rapidly to 95 C. After keeping the-autoclave inmotion for 4 hours, the polymerization product is taken out and purifiedas usual. 109 g. white, solid, polybutene of fibrous appearance areobtained,

suits:

Percent of the total Remarks polymer Acetone extract.'. 3 Low molecularweight amorphous polymers. Ether extract 42 Solid amorphous polymers.-Extraction residue 55 Highl or stalllne polymers solu la n hotn-heptane.

Example XXI 160 ml, of gasoline containing 5.7 g. of triethyl aluminum,and g. of butene-l (Phillips Petroleum Co. technical grade) areintroduced'into a 435 ml. autoclave.

The autoclave is heated to 81 C. and 1.8 g. of titanium,

tetrachloride dissolved in 35 ml. of gasoline are then added. Aspontaneous temperature-increase of some degrees OCCUI'S.

After about one hour a further addition of titanium tetrachloridedissolved in gasoline is made; a spontaneous temperature increase ofabout 10 C. occurs. The autoclave is kept in agitation for some hours ata temperature of -98" C.

Operating as in the foreging examples, .10 g. of a white solid productare obtained,.which softens at C. and

appears crystalline under the X-rays. The residue of the extraction withether corresponds to 46% of the obtained polymer and shows an intrinsicviscosity, calculated from measurements similar to those described inExample IX, of 1.44 ml./g.

Example XXI-A as in the foregoing examples, 86 g. of white solid productare obtained. Said product shows characteristics sim:

ilar to those described in Example XXI. Fibers are readily obtained fromthis product (the polymer mixture) by extrusion in a spinnerct undernitrogen pressure at temperatures close to thesoftening point. They showa mechanical strength of the same order as the fibers obtained fromploypropylene, but a higher elasticity;

The polymer mixture was fractionated, asv in preccd-. ing examples,using hot solvents.

The acetone extract amounting to 14% of the total polymer, consists ofoily, low molecular weight products.

The ether extract, which amounts to 35.5% of the total polymer obtainedconsists of a rubbery, amorphous solid having an intrinsic viscosity of0.35, corresponding to a molecular weight of about 7,000.

The residue of the ether extraction is completely extractable withn-heptane, with heating, and consists of a highly crystalline solidhaving a melting point of 125 C. and an intrinsic viscosity of 1.02,corresponding to a molecular weight of about 33,000.

Example XXII A solution of 8 g. tripropylaluminum in 90 ml. n-heptaneand 47 g. butene-l (Phillips pure grade) are introduced into a 435 ml.autoclave.

The autoclave is heated to 65 C. and a solution of 3.8 g. titaniumtetrachloride in 30 ml. n-heptane is injected under nitrogen pressure.The temperature rises spontaneously to about 75 C. The autoclave is thenkept in motion for about hours, at temperatures between 75 and 85 C.

22 g. of a white, solid polybutene are obtained after purification inthe usual way. It is fractionated by extraction with hot solvents, andthe following results are obtained:

Example XXIII A solution of 19.8 g. Al(n-C H in 450 ml. n-hep tane isintroduced into a 1100 ml autoclave filled with nitrogen. After adding'80 g. butene-l (Phillips pure grade) the autoclave is heated to 85 C.and at this point a solution of 7.6 g. TiCl, in 50 ml. n-heptane isinjected. The temperature goes up rapidly by about while the pressurefalls. The autoclave is then kept in motion for about 4 hours attemperatures between 85 and 95C.

After purification in the usual way the polymerization product yields44.2 g. polybutene, which are fractionated by extraction with hotsolvents, with the following results:

Percent 01 Intrinsic the total viscosity Remarks polymer Acetone extract12.4 Ether extract 40. 3 0. 28 Solid, amorphous. Residue 47. 3 0. 98Highly crystalline completely soluble in n heptane.

Example XXIV Percent of the total Remarks polymer Acetone extract 15. 6Low molecular weight amorphous polymers. Ether extract 48. 6 Solidamorphous polymers. n-lleptane extract 35. 7 Highly crystallinepolymers.

22 Example XXV ture decrease is no longer observed the gases arereleased and (while operating as in Example XXIV) 235 g. of polymer areobtained, corresponding to a 75% conversion of the employed propylene.The obtained product is made up mostly (84%) of crystallinepolypropylene, which can be separated from the non-crystalline productsby extraction with solvents.

Example XX V-A A glass vial containing 7 g. TiCl and 3 stainless steel.balls are introduied into a 2080 ml. stainless steel autoclave innitrogen atmosphere. A solution of 1.6 g. (0.013 moles Al(C H Cl in 500ml. n-hcptane is then added. After heating to 70 C., 350 g. propyleneare injected into the autoclave which is set in motion, thereby breakingthe glass vial. After 10 hours at' temperatures between and 85 C.,during which a continuous pressure fall is observed, the residual gasesare vented and 10 N1 propylene are recovered. The solid polymer obtainedweighs, after purification in the usual way, 315 g.

The extract with hot acetone is 10.8% of the total polymer. The etherextract, 16.2% of the total, is an amorphous, solid polypropylene, withintrinsic viscosity:0.43.

The n-heptane extract, 9.5% of the total, has an intrinsic viscosity of0.955, and has a crystallinity, as detected by X-rays measurements,higher than 50%. The extraction residue, 63.4% of the total polymer, isa high crystalline polypropylene, with an intrinsic viscosity of 2.05.

Example XXVI Into an oscillating autoclave of 1100 cm. capacity areintroduced two steel balls and a glass vial containing 1.85 I g. TiClUnder nitrogen atmosphere a solution of 4.95

63.6 g. polypropylene are obtained, which are frac-' tionated byextraction with hot solvents. The acetone extract corresponds to 5.1% ofthe total. The ether extract corresponds to 27.4% and consists of asolid,

amorphous polypropylene, with an intrinsic viscosity of 0.895. Theheptane extract corresponds to 14.9% of thetotal, contains more than 50%crystalline polypropylene} and shows, in tetralin solution at C., anintrinsic viscosity of 1.17. The residue is 52.6% of the total andconsists of a highly crystalline polypropylene having an intrinsicviscosity of 2.56. The obtained product has therefore a content ofcrystalline polypropylene of at least 60%.

Example XX VII 500 ml. of gasoline containing 12 g. diethyl aluminummonochloride, and 310 g. of propylene are introduced into a 2150 ml.autoclave, which is heated to-60" C.

Two portions of, respectively, 3.6 and 1.8 g. TiCl dissolved ingasoline, are then added. The reaction proceeds as described in theforegoing examples.

The reaction product consists of 248 g. of solid, white,

Agitation is continued, at

23 polypropylene. The yield is 80% on the introduced propylene and about95% on the converted propylene.

The acetone extract, Consisting of oily products, corresponds to of thepolymer obtained.

The ether extract, consisting vof a rubbery, amorphous solid,corresponds to 44% of the polymer obtained and has an intrinsicviscosity of 0.4.

The heptane extract corresponds to 16.4% of the polypropylene obtainedand consists vof a partially crystalline solid with intrinsic viscosity0.78.

The residue which remains after said extractions corresponds to 14.4% ofthe product obtained, has an intrinsic viscosity 1 1.53 and appearshighly crystalline when examined under the X-rays.

Example X X VIII Percent of Intrinsic the total viscosity Remarkspolymer Acetone extract 18.7 Olly. low molecularweight polymers.

Ether extract 43 0. 41 Amorphous solid. n-He tane extract.... 19 0. 7650% crystalline. Rest ue 19. 3 1. 87 Crystalline.

The raw polymer had therefore a crystallinity of about 29%.

Example XXIX Example XII is duplicated, with the exception that a 435ml. autoclave is employed, wherein g. (K mole) of a dialkylaluminummonochloride having an average molecular weight corresponding todidodecylaluminum monochloride, dissolved in 75 ml. anhydrous benzene,and 120 g. liquid propylene are introduced. The'auto clave is heated upto 72 C., while agitatingand then the solution of 1.9 g. titaniumtetrachloride in 20 ml. heptane is injected under nitrogen pressure.

A spontaneous temperature increase of some degrees occurs. A solution of1.9 g. titanium tetrachloride in 20 ml. gasoline is again injected.About 10 hours from the start, the catalyst is decomposed with methanolas in Example XII, and 68.5 g. of solid polymer are obtained,corresponding to a 57% conversion of the employed propylene. The polymerconsists, practically in its entirety (more than 90%) of amorphousproduct.

The acetone insoluble and ether soluble portion of the amorphous polymerhas a softening point of 55 C., an intrinsic viscosity of 0.25 and amolecular weight of about 5,000.

Example XXX 3.4 g. titanium tribrornide and a solutiori of 2.85 g.triethylaluminurn in 100 ml. n-heptane are introduced into a 435 ml.autoclave. 115 g. of a propylene-propane mixture, with 91% propylene,are then added. The autoclave is heated to 80-90 C. and kept in motionfor about 10 hours.

The polymerization product is purified as in the previous examples andgives 102 g. of a solid polymer,

The n-heptane extract, 20% of the total, has a crystallinity, asdetected by X-rays measurement, higher than 50%. i

The extraction residue, 34% of the total, is a highly crystallinepolypropylene.

Theobtained polymer had therefore a crystallinity.

of at least'44%.

Example XXXI Two steel balls, a glass vial containing 13 g. of titaniumtetrabromide' and a solution of 11.4 g.. of triethyl aluminum in 500 ml.of n-heptane are introduced under nitrogen into an'autoclave of 1750 ml.capacity. The

autoclave is heated, keeping it motionless, up to 63 C.

and at this point 280 g. ofpropylene are introduced into. Soonafterwards the autoclave is put the equipment. in motion, causing inthisway the breaking of the vial.

The temperature rises now spontaneously in a short lapse of time up to97 C. and'drops then again down to C. The autoclave is kept in agitationat this temperature for about ten hours. The unreacted gases are ventedand methanol is pumped into the autoclave.

The polypropylene is then purified in the usual manner; 249 g.'ofpolymer are obtained, equal to a conversion of 89% of the monomeremployed.

The acetone extract corresponds to 15.1% of thepoly- Example X XXII 5.15g. Til; and solution of 2.85 g. Al(C H in ml. heptane are filled into a435 ml. autoclave.

g. of a propylene-propane mixture, containing 91% propylene, are thenadded, the autoclave is heated to 8590 C. and kept in motion for about20 hours.

The polymerization product appears as a semi-solid, tacky mass, whichispurified and coagulated with methanol, 30 g. of solid, whitepolypropylene are thus obtained, while the evaporation of the solventused in the polym-t erization and purification steps yields 54.3 g.oily,'low molecular weight products.

Of the total 84.3 g. of product 64.5% is thus formed of oily products.

The solid polymer is fractionated by extraction with hot solvents. Theamount of crystalline polypropylene thereby obtained is 10% of the totalpolymer.

Example XXXIII motion for about 6.hours andthen the unreacted gases arevented, proceeding afterwards as described in the foregoing examples.

184 g. of propylene polymer are thus obtained which.

are fractionated by extraction with hot solvents.

The acetone extract corresponds to 20.4% of the polypropylene obtainedand consists of oily, low molecular weight products.

The ether extract corresponds to 22.7% of the poly- 25 mer obtained andconsists of an amorphous solid having, in tetralin solutions at 135 C.,an intrinsic viscosity equal to 0.43.

The heptane extract corresponds to 22% of the polymer obtained andconsists of partially crystalline solid with intrinsic viscosity 0.73.

The residue which remains after said extractions corresponds to 35% ofthe polymer obtained and consists of a powdery, highly crystalline solidhaving an intrinsic viscosity of 2.16.

Example XXXIV Into a 435 ml. autoclave two steel balls (1 inch diameter)and a glass vial containing 3.2 g. (i.e., 0.02 moles) vof solid vanadiumtrichloride are introduced. Then a solution of 5.7 g. triethyl aluminumin 100 ml. n-heptane is added under nitrogen. The autoclave is heated to81 C. and 98 g. pure liquid propylene are introduced; thereafter shakingof the autoclave is started, and continued for about 10 hours attemperatures in the range 81 to 90 C., while a steady, regular pressuredecrease may be noticed. After said time, 50 ml. methanol are pumpedinto the autoclave and 6 N1 of gas are collected. A solid, compactpolymer is discharged from the autoclave. It is first broken up in smallpieces and then treated with warm ether and hydrochloric acid, finallycoagulated with methanol and filtered. Since warm ether does notappreciably swell the obtained polymer, a further purification of thepolymer will be necessary, by treating it with warm benzene (whereby itwill be entirely swollen) and hydrochloric acid.

' The polymer is then coagulated with methanol and acetone, filtered,washed and dried by heating it under vacuum, to obtain 64 g. of solidwhite product. The obtained polymer is fractionated as in the precedingexample.

The acetone extract is 12.6% of the obtained polymer and is formed oflow molecular weight amorphous polymers.

, The ether extract, 21.4% of the total, is formed of amorphouspolypropylene with an intrinsic viscosity of 0.55. The heptane extract,24.1% of the total, contains more than 50% crystalline polypropylene (atthe X-rays examination). This fraction has an intrinsic viscosity of0.85, i.e., a molecular weight of about 25,000.

The extraction residue is a highly crystalline polypropylene having anintrinsic viscosity of 1.78, corresponding to a molecular weight ofabout 80,000.

The raw polypropylene obtained had therefore a content of crystallinepolymer of at least 54% Example XXX V Into a 435 ml. stainless steelshaking autoclave are placed two steel balls (1 inch diameter) and aglass vial containing-4.3 g. (0.02 moles) VCl The autoclave is thenclosed and evacuated and a solution of 5.7 g. (0.05 mole) triethylaluminum in 100 ml. n-heptane is then added under nitrogen pressure. Theautoclave is then heated without shaking to 81 C., when 118 g. of pureliquid propylene are introduced. Thereafter the glass vial is broken byshaking the autoclave,

which is kept in motion at temperatures varying from 81 to 83 C., whilea regular pressure decrease (from 41 to 13 atm.) is noticed. When apressure decrease is no longer observed, methanol is pumped in theautoclave in order to decompose the catalyst. The autoclave is thenvented and 5 N1 of gas are collected. The reaction product appears as asolid, light green mass, drenched with heptane and methanol. In order topurify the polymer from the inorganic products, it is treated with etherand hydrochloric acid, then coagulated with methanol, filtered andwashed with methanol. The obtained solid, white polymer is lastly driedby heating under reduced pressure. 77 g. of solid polymer are obtained,which corresponds to 65.2% of the used propylene. The obtained polymeris fractionated by extracting it in succession with hot acetone, etherand n-heptane.

The acetone extract, 10.1% of the total, consists of low molecularweight, oily polymers. The ether extract, 45.2% of the total, is a solidpolypropylene, amorphous under the X-rays, with an intrinsic viscosity,in tetralin solution at 135 C., of 0.82, corresponding to a molecularweight of about 24,000. The heptane extract, 16.45% of the total, is apolypropylene having an intrinsic viscosity of 1.31, i.e., a molecularweight of about 50,000. This fraction is approximately 50% crystalline.The extraction residue is a highly crystalline polypropylene, with anintrinsic viscosity of 1.88. The raw polymer obtained has therefore acrystallinity of about 36%.

Example XXXVI A solution of 11.40 g. triethyl-aluminum in 400 cc. nheptane, and 350 g. of a mixture containing 82% propylene and 18%propane are introduced, under nitrogen into an autoclave of 2000 cc.capacity. The autoclave is heated under stirring to C., and at thistemperature a solution of 6.8 g. V0Cl in cc. n-heptane is injected.

The temperature rises spontaneously to 87 C.,-while the pressure fallsrapidly. After about 5 hours methanol is pumped into the autoclave, andthe polymerization product is taken out. The product is then purifiedfrom the inorganic compounds present by heating with ether and hydrogenchloride and complete coagulation with methanol.

172.5 g. polypropylene are obtained, corresponding to 60% of the usedpropylene. The polymer is then fractionated by extraction with hotsolvents.

The acetone extract, 29% of the obtained polymer, is an amorphous, lowmolecular weight polypropylene.

The ether extract, 29.4% of the total, is an amorphous polypropylenewith an intrinsic viscosity of 0.52.

The heptane extract, having a crystallinity of about:

50%, shows an intrinsic viscosity of 1.15.

The extraction residue appears under the X-rays as a highly crystallinepolypropylene, and has an intrinsic viscosity of 2.1. fore acrystallinity of approximately 32.4%.

Example XXX Vll Into a stainless steel shaking autoclave of 435 ml.capacity 2 stainless steel balls (1 inch diameter) and a vial containing3.25 g. CrCl (i.e., 0.02 mole) are introduced. Into the closed autoclavea solution of 5.7g. (i.e., 0.05

mole) triethyl aluminum in 100 ml. n-heptane is added under nitrogen.The autoclave is then heated without shaking to 80 C. and 115 g. pureliquid propylene are.

introduced. Soon after, shaking is started and continued at temperaturesin the range 80 to C.

Forty hours from the start the unreacted propylene is discharged. Thereaction product is purified from the catalyst by washing with methanoland hydrochloric acid, and the solvents evaporated.

The obtained polymer is extracted with ether, which dissolves 37% of it;the dissolved fraction is completely amorphous. In the followingextraction with boiling heptane a fraction corresponding to 44% of thetotal is dissolved, which is 50% crystalline and shows an intrinsic aviscosity of 0.42.

The extraction residue is highly crystalline and has an intrinsicviscosity of 0.765. The raw product contains, therefore, approximately41% crystalline polypropylene. Example XXX VIII The raw polymer obtainedhad there- The autoclave is heated to 80 C..

'perature under stirring for about '20 hours.

27 Example XXXIX A glass vial containing 2.36 g. (0.012 mole) ZrCl,,

solution of 2.85 g. triethyl aluminum in 100 cc. n-heptane,

and two steel balls. are charged into a 435 cc. shaking;

autoclave under nitrogen atmosphere.

The autoclave is heated, while not in motion, to 73 C. and at thistemperature 70 gof a propylene-propane mixture containing 91% propyleneare then added. The autoclave is set in motion immediately thereafter soas to break the vial. After a few hours at 80 C., 7.6 g. of

polymer are obtained which are fractionated by extraction with hotsolvents.

By extraction with hot ether about 30% of the total product, i.e., theamorphous polypropylene is dissolved. In the following extraction withheptane of the product is dissolved, and is formed of apolypropylenecontaining more than 50% of crystalline polymer. Theextraction residue is a highly crystalline polypropylene. The rawproduct contains therefore about 50% of crystalline polypropylene.

Example XL Into a 435 ml. autoclave 2 steel balls and a vial containing4.7 g. (i.e., 0.02 mole) of ZrCI and 5.7 g. triethyl aluminum in 100 m1.n-heptane are introduced, then the autoclave is heated to 79 C. and 106g. pure liquidv propylene are admitted. Shaking of the autoclave is thentane, a fraction is dissolved which corresponds to 13.8% of the totalproduct. Under the X-rays, this fraction shows a content of crystallinepolymer of about 50%; the intrinsic viscosity, in tetralin solution at135 C., is 0.94.

The extraction residue is highly crystalline polypropylene with anintrinsic viscosity of 2.0 (i.e., a molecular weight of about 95,000).The raw product had, therefore, a content of crystalline polypropyleneof about 21%.

Example XL] Into a 2150 cc. autoclave are introduced under nitrogen 10g. of a mixture containing MoCl and 50% MoCl and a solution of 11.4 g.of triethyl aluminum in 500 cc. n-heptane.

Thereafter 365 g'. of propylene are added and the autoclave is heated to100 C., and maintained at this tem- The unreacted propylene is thenvented, and the reaction product is extracted from the autoclave andpurified by treatment with methanol and hydrogen chloride.

After evaporation of the solvents 115.3 g. of polypropylene areobtained, which are fractionated by hot so1- vent extraction. Theacetone extract corresponds to more than 90% of the total product and isformed of oily, low molecular weight products.

The residue after extraction with acetone is formed by approximately 50%of. a polypropylene, which is non crystallizable and which isextractable with ether, while the rest is a polypropylene which appearscrystalline under the X-rays.

Example XLII A glass vial containing 9 g. WCl and two steel balls areintroduced into a 2080 ml. oscillating autoclave. The autoclave is thenfilled with nitrogen anda solution of 11.4 g. AI(C H in 500 ml.n-heptane is added.

After heating to C., 140g. of a propylene-propane mixture containing 90%propylene is added and the autoclave is set in motion. After about 10hours, at 90-95 C., the polymerization product is taken out. It appearsas a liquid brown mass. After washing with acid and evaporation of thesolvent, 38 g. of oily products and 0.5 g. of'

solid polymer are obtained. The solid product appears approximately 50%crystalline when examined under the X-rays.

Example XLIII Into a 435 ml. autoclave twosteel balls and a glass vialcontaining 3.2 g. of solid vanadium trichloride are introduced.Operating as inthe foregoing examples 5.7 g.

(i.e., 0.05 mole) triethyl aluminum dissolved in 100 ml. heptane arethen added. The autoclave is then heated to 83 C., v110 g. of a mixtureof l-butene and Z-butenc with 70% of l-butene are introduced, and theautoclave is shaken to cause the breaking of the vial. After about 10hours of shaking at temperatures in the range 86 1 v to 96 C., theautoclave is discharged operating as in the foregoing examples. I

42 g. of a solid, fibrous, white substance are obtained; 21.5 g. thereof(i.e., 51.3%) can be extracted with ether and appear substantiallyamorphous under the X-rays.

The extraction residue, corresponding to 48.7%'of the. whole solidpolymer, when examined with theX-raysappears highly crystalline, andshows an intrinsic viscosity of 1.1.

Example XLIV A solution of. 11.4 g. triethyl aluminum in'400 cc. heptaneis introduced under nitrogen into an autoclave of about 2 literscapacity. 220 g. of a mixture of :l-butene.

and 2-butene containing 70% of the former are then added. The autoclaveis heated to 75 C. and at this temperature a solution of 4.4 VCl; in 100cc. pentane. is

added. The autoclave is kept in'motion for about 10,-

hours at temperatures between 75 and C.; the reaction product is thentaken out and purified as usual,

obtaining 90.2 g. polybutene which-are fractionated by- Example XLV Intoa 2150 ml. autoclave 2 steelballs and a vial containing 9.5 g. (i.e.,0.044 mole) ZrCl, are introduced. The autoclave is then evacuated and asolution of 45 g. (i.e., 0.1 mole) of a trialkyl. aluminum compound (ofan average molecular weight corresponding to tridecyl aluminum) in 450ml. anhydrous benzene is added. The. autoclave isheated, withoutshaking, to 82 C. and 222' g. propylene are introdcued. started to causebreakage of the vial, and continued for 14 hours at temperatures in therange 82 to 118 C., while a steady pressure decrease is noticed. Aftersaid time 100 ml. methanol are pumpedin and a reaction product very muchswollen with benzene is discharged. Theobtained product contains a largeproportion of relatively low vmolecular weight polymers which areamorphous, where- 8 g. Al(C H dissolved-in 200 ml. heptane and 200 g. ofpropylene-propanemixture containing 91% propylene are introduced into a.1100 ml. autoclave filled with nitrogen. After heating to 82 C., 3.85 g.VCl dissolved in 50 ml. -n-heptane are injected under nitrogen pressure.The temperature goes up rapidly to 100 C., while a fall of pressure canbe noticed. The autoclave is kept in motion for about 5 hours at atemperature between and C.

The polymerization product is then taken out; it'appears as a compactsolid mass swollen by the solvent. The product is purified by washingwith solvents acidified with hydrogen chloride and then completelycoagulated with Soon after, shaking is 29 methanol. 150.8 g. of a solid,white polymer are obtained, which are fractionated by extraction withhot solvents. The results of the fractionation are as follows:

The polymerization product contained therefore approximately 41%crystalline polymer.

Example XLVII Two steel balls and a vial containing 3.3 g. (i.e., 0.02mole) CrCl are introduced into a 435 ml. autoclave and then, undernitrogen atmosphere, a solution of 22.5 g. of a trialkyl aluminumcompound having an average molecular weight corresponding to tridecylaluminum, in 80 ml. anhydrous benzene is added. The autoclave is heatedwithout shaking to 89 C. and 100 g. propylene are then admitted. Soonafter, shaking is started and maintained for 14 hours at temperatures inthe range 89 to 105 C. The purification and separation of the polymer isthen carried out as in the preceding examples. The polymer which isricher in products of a lower molecular weight, contains only 14% ofproducts insoluble in ether, and extractable with hot heptane. Whenexamined under the X-rays, this fraction appears approximately as 50%crystalline.

Example XLVIII Into a 2350 ml. autoclave 2 steel balls and a vialcontaining 7.8 g. of liquid VCL; are introduced. The solution of 45 g.of a trialkyl aluminum (of an average molecular weight corresponding toaluminum tridecyl) in 500 m1. n-heptane is then added.

The autoclave is then heated to 87 butene (containing about 70% of1-butene) are added. Shaking of the autoclave is then started andcontinued for about hours, while keeping the temperature near 87 C.

Operating as in the foregoing examples 113 g. of a l-butene polymer areobtained which is found to be almost entirely amorphous. It contains infact less than 10% of crystalline product.

Example XLIX A solution of 17.5 g. Al(C H in 200 ml. n-heptane isintroduced into a 2080 ml. autoclave filled with nitrogen. 280 g. of apropylene-propane mixture containing 91% propylene are then added. Afterheating to 80 C., 2.2 g. VOCl dissolved in 50 ml. heptane are injectedunder nitrogen pressure. The temperature rises sharply to 90 C., whilethe pressure falls. After keeping the autoclave in motion for about 5hours, the product is taken out and purified as usual. By coagulationwith a large amount of methanol, 90 g. of polypropylene are obtained,which are fractionated by extraction with hot solvents. The followingfractions are obtained:

The obtained polymer was therefore approximately crystalline.

30 Example X LIX --A A solution of 0.02 mole trihexyl-aluminum in 250ml. heptane, and 80 g. l-butene are introduced in a litter autoclavefilled with nitrogen. After heating the autoclave to 90 C., a solutionof 1.38 g. (0.008 mole) VOCI in 50 ml. heptane is injected undernitrogen pressure. The temperature rises spontaneously to 95 C. Theautoclave is kept in motion for about 4 hours at this tempera ture; thereaction product is then taken out and the polymer isolated and purifiedin the usual way. 32.5 g. of polymer are obtained, which is prevalentlyamorphous;

by extracting it with hot ether, 8.8% of it remains as aresidue. Thisresidue appears highly crystalline when ex: amined under the X-rays.

Example L 7.6 g. of TiCl, dissolved in ml. n-heptane are added at 70 C.,while stirring. The reaction mixture is then c. and 260 g. of.

filtered under nitrogen atmosphere through a porous diaphragm G4(diameter of the pores 5 -15 microns) and the solid phase is washed onthe filter with a total of 120 ml. of a heptane solution containing 2%of triethyl aluminum. The solid phase is then suspended in 100 ml.n-heptane and introduced, while stirring under nitrogen pressure, into aglass vial which is then sealed. The vial,

together with 3 steel balls (1 inch diameter), and a solution of 11.4 g.triethylaluminum in 400 m1. n-heptane are then introduced into a 2150ml. autoclave. The autoclave is heated to 80 C. and 295 g. liquidpropylene are intro duced, the autoclave being soon after put in motion,while the temperature is kept between 80 and C. When a pressure decreaseno longer occurs, methanol is pumped into the autoclave and the gaseousproducts are released.

The reaction product is extracted from the autoclave as a nearlyentirely solid mass which is purified by the usual method and bytreatment with boiling toluene and concentrated HCl. After precipitationwith methanol and several washings with methanol, it is filtered anddried. 111 g. of polymer are thus obtained, which correspond to a 37.5%conversion of the employed propylene. More than half of the product(53.7%) is made up of crystalline .a

polypropylene, which may be separated from the noncrystalline product byextraction with solvents.

Example L1 80 ml. of the solution obtained by filtering the catalystused in the foregoing example are syphoned into a 310 ml. autoclave,under nitrogen pressure. The autoclave is heated up to 80 C., 76 g.liquid propylene are introduced and finally the autoclave is put inagitation. About 6 hours from the start of the polymerization, when aremarkable pressure decrease is no longer observed, methanol is pumpedinto the autoclave in order to decompose the catalyst, and the gaseousproducts are then vented. The reaction product extracted from theautoclave appears as a viscous, nearly colorless liquid. It iscoagulated with methanol to obtain a solid, gummy product which istreated as usual for its purification. It appears wholly amorphous underthe X-rays.

Example LII The black precipitate is then suspended in 250 ml. heptanecontaining 11.4 g. triethylaluminum. The whole is syphoned undernitrogen atmosphere into a 1000 ml. three two layers of which the upperis heptane containing in suspension, the flocky, easily filter-ablepolymer.

The precipitate is filtered and purified by boiling with acetonecontaining some hydrogen chloride, filtering and repeated washing withacetone. During such operation no loss in .weight is practicallyobserved. The obtained product appears very crystalline under the X-raysand starts melting above 210 C.

Example LIIl 7.3 g. vanadium tetrachloride dissolved in ml. nheptane areadded at 70 C., while stirring, to 11.4 g. of triethyl aluminumdissolved in 70 ml. n-heptane. The reaction mixture, consisting of aliquid phasev wherein a brown precipitate is in suspension, is filteredunder nitrogen atmosphere through a porous diaphragm whose pores have adiameter of 5 to 15 microns. The solid phase is then washed three timeson the filter with 30 ml. each time of a 1% solution of triethylaluminum in n-heptane. The solid phase is then suspended in 250 ml;n-heptane, and, while stirring, it is syphonedunder nitrogen atmospherein a previously deaerated glass flask provided with stirrer, droppingfunnel and refluxing cooler. In the flask kept under nitrogenatmosphere, 11.4 g. triethyl aluminum are then added. The temperature ofthe mixture is raised to 70 C. and .150 g. styrene are added whilestirring. Agitation is maintained for 4 hours at temperatures between'70and 75 C. The flask is then allowed to cool, the catalyst is decomposedwith'methanol and finally the reaction product is treated withhydrochloric acid.. The

liquid mass contains insuspension a solid, flocky polymer which is thenseparated by filtration.

The solid polymer is made up of two portions, one of which is soluble,theotherinsoluble, in acetone.

solid,.is found to be highly crystalline, whereas the acetone solubleportion is amorphous.

Example LIV The filtered solution, described in the foregoing example onthe preparation of the catalyst is introduced into a 1000 ml. flaskunder nitrogen. 100 m1. n-heptane are then added and the flask is heatedto 80 C. Next 150 g. styrene are added while stirring. The agitation iscontinued for 4 hours at temperatures in the range 70 'to 75 C. Aftercooling, the reaction product is treated with methanol and hydrogenchloride. Thus small amounts of styrene polymer (entirely amorphous) areseparated from the methanol solution. It is shown thereby that while thelittle dispersed catalyst, which may be separated by filtration asindicated in the Example LIII, yields a prevailingly crystallineproduct, the dispersed portion (which passes through the filter) yieldsa wholly amorphous polymer.

. Example LV By using purified titanium trichloride, with aluminumtriethyl or any of the other metallo-alkylcompounds, polymers of ahigher crystallinity are obtained.

7 g. of TiCl purified of the traces of titanium tetrachloride byrepeated washing in nitrogen atmosphere with anhydrous n-heptane, areintroduced in a 2080 ml. autoclave, 11.4 g., triethyl aluminum in 500cc. n-heptane, and 310 g. pure propylene are added. The autoclave isheated to 80 C. and kept in motion for about 10 hours at thistemperature.

The polymerization product is then taken out and purified as usual. 240g, of polypropylene are obtained which The insoluble portion,corresponding to 68% of the whole 32 are fractionated with hot solvents,with the following results:

Percent 01 Percent crystalline the total Acetone extract 3. 5 Etherextract- 3. 4 Amorphous. n-Heptano extract 4. 0 50. Extraction residue-89.1 Highly crystalline.

The obtained polymer has therefore a crystallinity of about9l%.

Example LVI are fractionated by extraction with boiling solvents, withthe following results:

Intrinsic Percent of viscosity Remarks the total in totmlin I at 0.

Acetone extract 6. 15 Oily low mol. wt.

po ymers. Ether extract 53. 75 0. 565 Amorphous solid. Heptane extract17.80 1. 2 Crystalline. Extraction residue.... 22. 30 2. 76 Highlycrystalline.

The raw polymer had therefore a crystallinity, as determined by X-raysmeasurements, of about 31%. The infra-red spectra of laminae, preparedfrom the ether ex tract and from the heptane extract indicate thepresence in the polymer of monosubstitutedphenyl groups.

In a preferred embodiment, the unsaturated hydrocarbon polymerizedcontains from 3 to 8 carbon atoms.

By state of aggregation as used herein, is meant the various states ofmatter commonly referred to as true solids (that is, crystalline),liquid and gaseous, i.e., states in which atoms, ions and/ or moleculesare aggregated to one another to form larger particles of matter. Byamorphous" we mean that. state between true solid and true liquid inwhich matter shows no distinct crystal lattice but does not flow due toits high viscosity.

By state of dispersion as used herein,.we meanthe degree to which matterconsisting of aggregates as aforesaid is divided up into particles ofvarious sizes ranging from a monomolecular dispersion, as in a truesolution, to a coarse dispersion by which we understand a dispersion ofparticles of a size above a few microns. In,-

termediate degrees of dispersion comprise matter'divided:

low a few microns, i.e., particles which are prevalently dispersed inthe colloidal state or, in the extreme case, true solutions.

Inert solvents used for preparing the polymerization catalyst when thesame is not prepared in the monomeric unsaturated hydrocarbon, and theconditions used, including the temperatures and pressures used, are thesame as disclosed in our aforementioned copending applications.

The method of precipitating the polymer with methanol, and of solventfractionation described in the examples are chiefly intended forestablishing the total amount of amorphous and crystalline polymers.

In practice, in the production of commercial polymers, particularly ofhighly crystalline products, the high molecular weight polymer,spontaneously separated from the solvent. which will only retain thesmall amounts of oily polymers that may be present, may be simply washedwith .alcohols to eliminate the enclosed catalyst.

For all those uses where a specially high purity is not required aswashing with a hydrocarbon solvent may be substituted for the alcoholwashing.

After drying the product will be ready for use.

It will be apparent that various changes and modifications may be madein practicing the invention and, therefore, it is to be understood thatthe invention is not intended to be limited except as defined in the appnded claims.

What is claimed is:

1. A process for polymerizing butene-l with a catalyst prepared from (1)a solid, violet crystalline material comprising violet crystallinetitanium trichloride and (2) a dialkyl aluminum monohalide in which thealkyl groups contain from 2 to 4 carbon atoms, which process comprisesforming the catalyst by mixing (1) and (2) at a temperature up to 90 C.and in a liquid diluent substantially inert to the dialkyl aluminummonohalide, to obtain a catalyst in which none of the titanium isreduced below the trivalent state, and then polymerizing butene-l withsaid catalyst at a temperature between 20 C. and

34 120 C. in a liquid diluent substantially inert to the dialkylaluminum monohalide.

2. A process according to claim 1, characterized in that the catalyst isprepared from (1) a solid, violet crystalline material comprising violetcrystalline titanium trichloride and (2) a dialkyl aluminummonochloride.

3. A process according to claim 1, characterized in that the catalyst isprepared from (1) a solid, violet crystalline material comprising violetcrystalline titanium trichloride and (2) diethyl aluminum monochloride.

References Cited by the Examiner UNITED STATES PATENTS 2,721,189 10/55Anderson et al 260-93.7 2,825,721 3/58 Hogan et al 260-93] 2,858,902ll/58 Cottle 260-93] 2,862,917 12/58 Anderson et al. 26094.9 2,905,6459/59 Anderson et al 260-94.9

JOSEPH L. SCHOFER, Primary Examiner.

B. E. LANHAM, LESLIE H. GASTON, MILTON LIEBERMAN, WILLIAM H. SHORT,Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,197,452 July 27, 1965 Giulio Natta et al.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 3, line 43, for "1965" read 1955 column 4, line 43, for "polymer"read polymers column 6, line 19, after "zirconium" strike out the comma;line 47, for "difficulty" read difficultly columns 7 and 8, TABLE 2,sixth column, line 1 thereof, for "(17)" read (15) column 9, line 67,for "iregular" read irregular column 11, TABLE 6, in the heading, line2, for "alumin" read alumincolumn 17, line 26, for "28.8" read 28.2column 22, line 22, for "introduied" read introduced column 26, line 15,for "11.40" read 11.4

Signed and sealed this 20th day of September 1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. A PROCESS FOR POLYMERIZING BUTENE-1 WITH A CATALYST PREPARED FROM (1)A SOLID, VIOLET CRYSTALLINE MATERIAL COMPRISING VIOLET CRYSTALLINETITANIUM TRICHLORIDE AND (2) A DIALKYL ALUMINUM MONOHALIDE IN WHICH THEALKYL GROUPS CONTAIN FROM 2 TO 4 CARBON ATOMS, WHICH PROCESS COMPRISESFORMING THE CATALYST BY MIXING (1) AND (2) AT A TEMPERATURE UP TO 90*C.AND IN A LIQUID DILUENT SUBSTANTIALLY INERT TO THE DIALKYL ALUMINUMMONOHALDIE, TO OBTAIN A CATALYST IN WHICH NONE OF THE TITANIUM ISREDUCED BELOW THE TRIVALENT STATE, AND THEN POLYMERIZING BUTENE-1 WITHSAID CATALYST AT A TEMPERATURE BETWEEN 20*C. AND 120*C. IN A LIQUIDDILUENT SUBSTANTIALLY INERT TO THE DIALKYL ALUMINUM MONOHALIDE.